Ecological studies on organic, integrated and chemical farming in wheat under soybean-wheat cropping system for sustainable agro-ecosystem

The field experiment on wheat in soybean-wheat system was conducted during rabi 2001–02 and 2002–03 by keeping organic (pure), integrated (partial) and chemical farming systems at the experimental farm of the department of Agronomy and Agrometeorology, Punjab Agricultural University, Ludhiana on sandy loam soil. In soybean-wheat sequence on an average, M₁₀-M₂₀-RI (FYM 10 t/ha to soybean, 20 t/ha to wheat and incorporation of residues of both crops), M₅-M₁₅-GM-RI (GM-green manuring), Rec.-GM-RI (Rec.-recommended chemical fertilizers) and Rec.-GM-R0 (R0- residue removed), pure and partial organic farming treatments gave 7.9, 4.7, 7.2 and 5.8 per cent higher wheat grain yield than the recommended chemical fertilizer (Rec.) treatment. M₁₀-M₂₀-RI, M₅-M₁₅-GM-RI, Rec.-GM-RI and Rec.-GM-R0, pure and partial organic farming treatments produced significantly higher plant height, dry matter accumulation, leaf area index, PARI (%), chlorophyll content (SPAD reading), ear length and number of grains/ear. Pure and partial organic farming treatments showed less canopy and soil temperature as compared to chemical farming treatments.